Mitochondrial Function in the Peri-operative Setting: an Observational Study

Complications after surgery are common and a burden for patients and health services. Therefore it is important that clinicians improve surgical outcomes. Mitochondria are the part of the body's cells that manage energy. Research has already shown that how our body's mitochondria behave can predict who survives in intensive care patients. The investigators think this could also predict who is more likely to develop complications after surgery. Therefore a study has been designed to find out if changes in mitochondria are related to postoperative complications. This will help doctors improve how they prepare patients for surgery and potentially how they manage their treatment, and result in improving outcomes for patients after surgery.

This study will recruit patients scheduled for major abdominal surgery as part of their treatment. The investigators will take samples of breath, blood and muscle to measure changes in mitochondria from the day before surgery to 7 days postoperatively. The muscle samples will only be taken when the patient is asleep having their operation. These samples will be used to analyse mitochondria. This study will be in two phases. Phase 1 is a pilot of up to 10 patients focussed on feasibility. Following this there will be an interim data analysis. The results may allow further optimisation to reduce the patient burden, eg reduction in sampling frequency, or avoiding need for muscle biopsy. The second phase will be a full cohort study of up to 40 patients, focussed on association of mitochondrial markers with clinical outcomes, such as postoperative complications, oxygen levels, pain, confusion and length of intensive care stay.

The results of this study could improve how doctors select and prepare patients for surgery. It may also affect how doctors manage their treatment during and after operations. This could result in reducing complications and illness burden for patients after surgery.